A telephone in which a scanning of this type is performed is known from EP 0 522 885.
The mobile station is supplied with power by a rechargeable battery and its autonomy i.e. the time during which it can remain separated from the base station, depends on the size of the battery and on the power consumption of the circuits of the mobile station not only in the operation mode, but also in the standby mode. When the user wishes to use the telephone line and touches a key for this purpose, or when a call arrives on the line, a "link set-up request" is transmitted and repeated for setting up a radio connection called link between the base station and the mobile station; the link is not set up immediately, but only when a scanning has detected this request for setting up the link. The more the scanning takes place, the more the response time is reduced, but the more significant is the power consumption in the standby mode.
Various channels are defined and, depending on the circumstances, one wishes to be able to select a different channel. There are, for example, 10 channels. Before any use, a scanning is thus to be performed to select a channel which will cause a delay. The scanning is one of the critical points which determine the quality of a cordless telephone, because the response time depends thereon and also the autonomy of the mobile station, or the size of the battery, and the reliability of the set-up of the radio link.